Members of an amateur radio group say they’ve solved the mystery of car key fobs frequently failing to function in the 600 block of Dempster Street in Evanston.

A report on the website of the American Radio Relay League says police received reports of the issue earlier this year in which some drivers parked their cars on the block only to be unable to get the doors open when they returned to drive away.

Once the cars were towed off the block, the key fobs started working again. Some people also reported trouble using their cell phones while on the block.

Police contacted the ARRL, which sent Central Division Director Kermit Carlson to the scene with a noise signature receiver which determined that the power supply for a store’s neon sign at mid-block was producing substantial interferience on the frequencies used by the auto key fobs.

Carlson says the store owner agreed to turn off the sign if the problems recurred.

Bill Smith is the editor and publisher of Evanston Now.

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  1. The cars had to be towed off

    The cars had to be towed off the block? Do cars not have manual key locks on the doors anymore? My car must not be fancy enough…

    1. Keyless in Evanston

      Some cars, I'm told, don't have old fashioned keys anymore. But mine's not that fancy either.

      — Bill

      1. Return to physical “keys”

        With stories about hacking of car's electrical systems [breakins and taking control of steering], how long before cars come with devices where you have to insert a "key" that bridges a gap [that electronic signals can't bridge], before the car can be started/moved ?

        The "old" becomes "new" again.

        Does not sound like that would have helped here but if something as simple as a neon sign can cause this problem, what other accidental or purposed effects will happen ?

    2. Pretty much any car or truck

      Pretty much any car or truck (with a few exceptions) made since 1997 have an 'transponder key' or as I like to call them '$100 keys'. Used to you could only get them programmed at a dealer, now any locksmith, and I think Home Improvement Stores can make them, but they are still expensive. Anyways, they are an anti-theft device, so if an 'authorized key' is not present, the car or truck will not start. The computers on the cars pick up the transponders on the keys, then allow the car or truck to start. I had an 2007 F-150 XL, that was featureless except for AC, and Automatic Trans, but it had transponder keys, and a red flashing light on the dash to ward off theives.


    3. Emergency key

      So you forget to replace the battery in your smart key. You have to call a wrecker to tow your car to the dealership? My Dodge key has a built in regular key and an external keyhole in the door for just such emergencies.

      1. Most cars with key fobs have

        Most cars with key fobs have a spot in the car where you can put the key and it will recognize it even with a dead battery. 

      2. Key Fobs

        While my car has an "emergency key" it will only unlock the driver's side door.  There is no ignition key, just a "start" button.  Had I parked where that RFI occurred my car would probably have to be towed too.

  2. Nice work ARRL
    I’m impressed and glad that ARRL was able to find the source of the interference, and glad to hear the business owner is willing to turn off the sign if the problem continues. Imagine how drawn out and expensive a lawsuit to get the sign turned off would be; glad that’s not going to be a problem!

    1. Backup transponder mode
      All push button start Chrysler/Dodge/Jeep/Ram vehicles have a backup transponder mode, if the fob battery dies. You use the emergency key that is stored in the fob to enter the vehicle (the alarm will go off), then push the start button with the other end of the fob (the end that you didn’t get the emergency key out of). Viola! The vehicle starts and runs, and the alarm is silenced. This is described in the user’s manual and I think on a tips card that is attached to the fobs when the vehicle is delivered from the dealer.

      If you have an older rotary ignition, just use the key to open the driver’s door (alarm goes off), and then place the key in the ignition and start the vehicle. The engine will continue to run and the alarm will turn off.

      Both of these systems use a transponder pill that is embedded in the key fob, that requires no battery to run, similar to a SpeedPass RFID fob.

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